step(ci,(ci,s),tm(s,[pri(naught,[]),pri(naught,[])],pri(lst,[pri(h,[ctxm(beta_2_,u,bsn,i_bsn,i_bsn)]),pri(h,[pri(lst,[pri(h,[ctxm(beta_2_,u,bsn,i_bsn,i_bsn)]),ctxm(beta_2_,r,dom, (dom,r,beta_2_), (dom,r,beta_2_))])]),ctxm(beta_2_,r,dom, (dom,r,beta_2_), (dom,r,beta_2_)),ctxm(beta_2_,u,d_2, (i,d_2), (c,d_2)),ctxm(beta_2_,u,d_5, (i,d_5), (c,d_5))]))).